Vaporizer unit and tray



y 14, 1953 A. s. ALLEN 2,645,607

VAPORIZER UNIT AND TRAY Filed Oct. 30, 1948 5 Sheets-Sheet l INVENTOR G)I Albrl S flllen July 14, 1953 s, ALLEN 2,645,607

VAPORIZER UNIT AND TRAY Filed Oct. 30, 1948 3 Sheets-Sheet 2 ei'i AS..HZZen ATTO July 14, 1953 A. s. ALLEN 2,645,

VAPORIZER UNIT AND TRAY Filed Oct. 30, 1948 3 Sheets-Sheet. 5

INVENTOR Albeit S. flllen ATTOR ZEYS l atented July 14, 1 953;

VAPORIZER UNIT AND TRAY Albert S. Allen, Springfield, Mo., assignor toUnited States Hoffman Machinery Corporation,

Syracuse, N. Y.

Application October 30, 1948, Serial No. 57,465

12 Claims.

This invention relates to the conditioning of oil and the like, and morein particular to a system for removing foreign materials from oil such,for example as oils which are used in transformers, refrigerators,turbines, and engines. This invention also relates particularly to avaporizer for removing volatile substances from oil or the like.

An object of this invention is to provide an improved system forreconditioning oil wherein the disadvantages of the prior art systemsare avoided, and wherein extremely efficient operation is obtained.Afurther object is to provide an efiicient and dependable arrangementfor removing volatile substances from a liquid such as oil. A furtherobject is to provide for the efficient heating of a liquid such as oilas it passes in a thin stream through'the heating zone. A further objectis to carry out the above with absolute safety and yet with assurancethat thorough treatment is obtained. A further obobject is toprovideapparatus for carrying out the above which is light in weight,sturdy and compact in construction, efiicient and dependable inoperation, and inexpensive to manufacture, operate and maintain. Theseand other objects will be in part obvious and in part pointed out below.

The invention accordingly consists in the features of construction,combinations of elements, arrangements of parts and in the'several stepsand relation and order of each of the same to one or more of the others,all as will be illustratively described herein, and the scope of theapplication of which will be indicated in the following claims.=

In the drawings:

Figure 1 is a schematic view showing an oil conditioning systemincorporating the present invention;

Figure 2 is a side elevation with parts in section of a vaporizer unitwhich is part of the system of Figure 1;,

Figure 3 is a perspective view of one of the trays of the unit of Figure2; and,

Figure 4 is a vertical section showing certain of the structure of thetray; of Figure 3.

In many different types of apparatus, oilis used under circumstanceswherein purity is important, but where the oil is subjected tocontamination by liquids, gases or solid particles. j For example, oilis used as an electric insulator in transformers, circuit breakers, andcables, and it is quite important that the moisture content be kept atan extremely low value so that the desirable dielectric properties ofthe oil are maintained; and this oil may become contaminated with dirt,or where electric sparks occur the oil. may partially burn to formcarbon particles and. this may interfere with the dielectric propertieof the oil and with ability of the oil to circulate Similarly, inrefrigeration systems it is important that the oil be kept free of watervapor and other; contamination such as dirt particles. The lu bricatingoil in internal combustion engines is apt to become diluted with thefuel and it may become contaminated with dirt and carbon particles. Theremoval of contamination so as to insure the desired purity of theseoils is referred. to as reconditioning of oil; and it is an object ofthe present invention to provide an improved system for reconditioningthese and similar oils or like liquids.

In accordance with the present invention a, unitary system is providedwhich includes a filter unit for first removing the solid particles fromthe oil and a vaporizer unit within which the oil is heated so as todrive off vapors and gases.

The oil is pumped through the filter unit and it then flows in acontrolled manner into the vaporizer unit where it flows in thin streamsor layers down a. plurality of serially related trays, and the trays areheatedso that the temperature of the oil is gradually raised. The oilpasses from the vaporizing unit in heat-exchange relationship with theoil passing to the vaporizer unit so that a relatively low temperaturesupply of pure oil is provided.

Referring particularly to Figure 1 of the drawings wherein oneembodiment of the invention is shown schematically, the oil to beconditioned is drawn in (see the lower right-hand portion of figure)through a pipe 2 by a rotary pump 4. Pump 4 delivers the oilthrough apipe 5 having normally open valve 1 therein to a filter unit 6 of aknown type. Within the filter unit the oil is subjected to a thoroughfiltering action so as to remove all insoluble materials and particlesand the oil then passes from the filter unit through a pipe 8. Pipe 8has a normally opened valve 9 therein and the oil fiows from pipe 9through a pipe II, a heat exchanger iii, a float- .controlled valve I2and a pipe [3 to the preheater section, 14 of a vaporizer l6. Vaporizerit has a tank l5 at the bottom of which the preheater section is formedby a dished or downwardly concave wall 28. While within the preheatersection the oil is preheated by an electric heater unit 18 and it thenpasses through a pair of aligned pipes 20 to a vertical pipe 22 andthence upwardly to a header 24.

The preheated oil passes from a header 24 through twelve distributionpipes 25 (only three of which appear in the schematic showing ofFigure 1) into the uppermost of a set of vaporizing trays 26 which arerepresented schematically and which will be described in detail below.The oil flows in a thin layer or sheet form from one tray to the nextbeneath it, and at the bottom of the lowest tray it falls onto a. sump29 formed by the dished wall 28 which separates the preheater section [4from the main portion of the vaporizer tank 15. While flowing down thetrays the oil is heated by the heat from a set of strip heaters 30 fixedto the outer wall of the vaporizer tank. Thus, the filtered oil issubjected to a gradual heating while flowing in a thin sheet form so asto drive off all volatile liquids such as hydrocarbons and water as wellas gases such as air which are contained in the oil, and .pure oilcollects in sump 29.

At the top of the vaporizer tank there is a. finned pipe 32 throughwhich the gases and vapors pass and are cooled and they then passdownwardly to a tank 34; and, during this passage the vapors arerecondensed as liquids which collect in this tank. The uncondensedvapors and gases are pumped from the top of tank 34 through a pipe 35 bya vacuum pump 36 and are discharged through a check valve 38. The pureoil is withdrawn from sump 29 in the bottom of the vaporizer tankthrough a discharge pipe 40 connected to the center of wall 28 by a pump42. The oil then passes through heat exchanger IO in heat-exchangerelationship with the oil passing to the vaporizer, thus, to heat theincoming oil and to cool the conditioned oil; and pure oil passes fromthe heat exchanger through a pipe 44.

It is desirable to maintain a pool of oil in sump 29 so that oil can beremoved as desired by operating the positive discharge pump 42; and,therefore valve I2 is so controlled that oil is delivered to thevaporizer unit at only the rate necessary to maintain the desired levelof oil in the sump. Accordingly, valve 12 has its float 43 positioned ina tank 46 which is connected at its bottom to oil sump 29 through pipes48 lowered so that valve l2is moved toward its fully opened position,and when the oil level in the sump and the float rise and valve 12 ismoved toward its fully closed position.

Pump 4 is of the positive displacement 'type so that oil is pumpedthroughthe filter unit at a constant rate, and when valve l2 restrictsthe flow the pressure tends to'build up in pipe H. However, pipe II isconnected to pipe 2 through a pipe 52 having a pressure relief valve 54therein, and when the pressure in pipe ll reaches a predetermined valuevalve 54 opens'and oil flows through pipe 52 to pipe 2; in this way theoil in excess of that which passes through valve l2 returns to pipe 2and is recirculated through the filter unit. This arrangement not onlygives accurate control upon the supply of oil to the vaporizer unit, butit also has the advantage that the recirculation of oil through thefilter unit raises still higher the standard of purity of the oil. Undersome circumstances it is desirable to operate the system without thefilter unit, and therefore, the discharge pipe from pump 4 is connectedto pipe ll through a pipe 58 having a normally closed valve 60 therein;and the filter unit is lay-passed by closing valves 1 and 9, and byopening valve 60 so that the oil from pump 4 passes directly to pipe II.

The details of construction of the vaporizer unit are shown in Figures2, 3 and 4 where the parts are numbered to correspond with Figure 1.Tank I5 is covered by heat insulation 62 and the unit is mounted onthree legs 64. The top of tank I5 is closed by a removable cover 56which has a gasket 68 around its periphery and is clamped in place by aplurality of bolts 10. There are five pairs of the trays with each pairbeing formed by a somewhat irusto-conical tray 12 which slantsdownwardly and radially outwardly, and a somewhat similar tray 14 whichslants downwardly and radially inwardly. Referring particularly toFigure 3 each tray 12 is formed by four segmental tray units or sections15, each of which is formed by .a sloping bottom wall 16 which slopesaway from the center axis, an arcuate side wall 18,and two radial sidewalls '80 '(see also Figure '4). Each wall'80 has two 'springpockets 82and 84 positioned respectively adjacent the inner and outer peripheriesof the tray, and each of these pocketsreceives the end of a spacerspring. the two adjacent mating pockets82-receive the two ends of'aspacer spring 86, and the two adjacent mating pockets 84 receive theopposite ends of a spacer spring 88. Concentric-with pockets 82 areholes through which extends a boltSO havinga nut"92 thereon, andt'hecentral portion of each side wall '80 has a similar hole therein whichreceives a bolt 94 having a nut '96. Thus, as shown in Figure 4 springs85.and 88 urge the 'tray segments or sections apart, but bolts 90 :and94 limit this movement. Wall Hi'has onitsupper surface a web structure91 which tends-to spread the oil asthe oil flows along'the'bottom wallof the tray. Adjacent the center and ends of walls '18 there are oiloutlet or drain openings I00 in the bottom wall through which-the oilflows to the tray 14 beneath it. As indicated above in connection withthe discussion of Figure l, oil is supplied to the vaporizer unit at thecenter of the top tray 12 through twelve distribution pipes 25.

Referring now to "Figure "3 wherein the twelve tray sections are shown,each of the twelve-distribution-pipes delivers oil to a traysection andthe oilin each section flows outwardly-and downwardly to its drainopening I00.

Each of trays 14 (Figure 2) is similar in construction-to trays 12except that the trays 14 slope toward the center axis; thus, each tray'14 is formed by four sections 10! andhasa sloping bottom wall I02, anarcuate side wall I04, and two radial walls. Adjacent the innerperiphery of eac'htray are oil outlet or drain openings I08 throughwhich oil flows from the tray.

The arcuate walls of the tray sections are'of thecontour of theinnersurface of tank-l5, and the lower-most tray rests at itsouter peripheryupon wall 28 and the other trays are stacked one upon another withtheir'arcuate walls contacting each other. In assembly, nuts 92 and 95are tightened sufiiciently to reducethe 'overall efiective diameter ofeach of the trays to something less-than the inner diameter of tank l5.This compresses springs 86 and88,'and the construction is such that thetrays are then relatively rig'idan'd they may be lowered withoutdifficulty .into tank -l5. After each-tray is properly positioned,.itsnuts-92 I and 96 are loosened so that its springs 86 andflBare no longerrestrained and they urge the tray sections apart. This increases theoverall effective diameter of the :tray so that the arcuatewall.of.each. -1tray section is urged tightly against the adjacentportion of the inner surface of tank. l5. lhu's, after assembly thetrays are easily put intoplace andthen are held in fixed relationshipwithin the tankcAs indicated above, the contour of the arcuate' walls ofthe tray sections is the same as that ofthezjinner surface of tanki5,.and-this'insures ithat ;a good heat-exchange .relationshipiisestablished between the tank wall and each'o'f thetray sections. Heaters35] are heldby .clampbars H0 and bolts Iii tightly against.theJoute'rE'surface of tank [5, and therefore, the heat from the heaterspasses readily to the trays. The trays are of cast aluminum and the heatdistributes itself throughout the entire bottom surface of each traysection. Thus, the oil flowing down the trays in thin streams issubjected to an even heating effect so that vapors and gases are drivenfrom it.

The vaporizer may be used without the filter unit when it is unnecessaryto remove solid particles. For example, the vaporizer may be used totreat either sour or sweet crude oil for removing such constituents ashydrogen sulphide, butane, propane and water, and it may also be usedfor removing sulphur. Tests have indicated that the sulphur content maybe reduced from five percent to as low as 1.25 percent. For certainprocesses a filter unit is connected to pipe 44 so that the oil or thelike is subjected to a filtering action after passing through theevaporator.

As many possible embodiments may be made of the mechanical features ofthe above invention and as the art herein described might be varied invarious parts, all without departing from the scope of the invention, itis to be understood that all matter hereinabove set forth, or shown inthe accompanying drawings is to be interpreted as illustrative and notin a limiting sense.

I claim:

1. A vaporizer unit comprising a substantially cylindrical tank having avertical axis and a heat conducting side wall, a plurality of trayswithin said tank positioned one above the other and having peripheralsurfaces which conform to and tightly engage the inner surface of saidside wall, each of said trays comprising a plurality of tray sectionsdivided from each other along radial planes, and pockets adjacent theends of the dividing walls of said section, a plurality of spacersprings in said pockets to urge said sections away from each othertransversely of said planes, a plurality of bolts to hold said sectionstogether, a pre-heater section in the bottom of said tank formed by aconcave wall positioned directly beneath the lowest tray and spacedupwardly from the bottom wall of the tank, a pipe assembly extendingfrom said pre-heater section to the top of said tank, and having oildischarge means directing oil into the uppermost of said trays, andheater means on the outer surface of said side wall to heat the trays.

2. In a vaporizer unit the combination with tank means having aheat-conducting side wall of a plurality of trays within said tankpositioned one above the other, each of said trays comprising aplurality of tray sections divided from each other along radial planes,and spring means urging said sections away from each other transverselyof said planes, and heater means on the outer surface of said wall toheat the trays.

3. A vaporizer unit comprising a substantially cylindrical tank having aheat conducting side wall, a plurality of trays positioned one above:the other in said tank having peripheral surfaces which conform to andtightly engage the inner surface of said side wall, each of saidtrays'comprising a plurality of tray sections separated along radialplanes and provided with a plurality of circumferential baflies andradial dividers, a pair of well portions along each edge of said traysections, coil springs mounted therein'to' urge the tray sections awayfrom each other.

4. In a vaporizer the combination of a substantially cylindrical tank, aplurality of traysnD- sitioned one above the other within said tank,each of said trays being formed by four substantially identical traysections held together by a plurality of bolts and urged toward a spacedrelationship by a plurality of springs acting in cooperation with saidbolts.

5. A vaporizer unit comprising a substantially cylindrical tank having avertical axis and a heatconducting side wall, a plurality of traysWithin said tank positioned one above the other and having peripheralsurfaces which conform to and tightly engage the inner surface of saidside wall, each of said trays comprising a plurality of tray sectionsdivided from each other along radial planes and spring means to urgesaid sections away from each other transversely of said planes, andheater means on the outer surface of said side wall to heat the trays.

6. A vaporizer unit as described in claim 5 wherein at each of saidradial planes there are two wall portions of the adjacent tray sectionseach of which has a spring pocket therein, and wherein a coil spring ispositioned with its two ends positioned respectively within said pocketsthereby to provide the spring means urging the tray sections away fromeach other.

7. A vaporizer unit as described in claim 5 which includes, a preheatersection in the bottom of said tank formed by a concave wall positioneddirectly beneath the lowest tray and spaced upwardly from the bottomwall of the tank, and a pipe assembly extending from said preheatersection to the top of said tank, and having oil discharge meansdirecting oil into the uppermost of said trays.

8. A vaporizer unit as described in claim 5 wherein said trays are oftwo types alternately positioned with one type having a downwardly andradially outwardly slanting bottom wall and the other type having adownwardly and radially inwardly slanting bottom wall, each of saidtrays having an arcuate peripheral wall which is a segment of acylinder.

9. A vaporizer unit as described in claim 8 wherein each of said traysis formed by four substantially identical tray sections held together bya plurality of bolts and urged toward a spaced relationship by aplurality of springs.

10. A vaporizer tray having a substantially circular periphery andformed by more than two substantially identical tray sections each ofwhich has two radial side walls with each wall having adjacent its endspockets which receive the ends of spacer springs, and means holding saidtray sections together.

11. A vaporizer tray having an arcuate peripheral wall which issubstantially a segment of a cylinder, formed by a plurality ofsubstantially identical tray sectionseach of which has two radial sidewalls with each Wall having adjacent its ends pockets which receivesprings which urge said sections toward a spaced relationship :and meansholding said tray sections together.

12. A vaporizer tray as described in claim 11 wherein saidtray sectionsnumber four andzhave peripheral walls adapted to conform to and tightlyengage the side walls of a vaporizer tank.

ALBERT S. ALIEN.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,023,450 Wheeler Apr. 16, 1912 Number 8 Name Date AlexanderSept. 25, 1917 .Jones Dec. 27, 1927 Primrose Aug. 6, 1929 Omanetal- Jan.9, 1934 .Otto et a1. July 31, 1934 Stephens et al Nov. 5, 1935 .AdamsMay 5, 1942 .Smith July '7, 1942 Buyer: Apr. 4, 1944 Beach July 11, 1944.McAllister etal. Oct. 17, 1944 LaBrecque Aug. 12, 1947

1. A VAPORIZER UNIT COMPRISING A SUBSTANTIALLY CYLINDRICAL TANK HAVING AVERTICAL AXIS AND A HEAT CONDUCTING SIDE WALL, A PLURALITY OF TRAYSWITHIN SAID TANK POSITIONED ONE ABOVE THE OTHER AND HAVING PERIPHERALSURFACES WHICH CONFORM TO AND TIGHTLY ENGAGE THE INNER SURFACE OF SAIDSIDE WALL, EACH OF SAID TRAYS COMPRISING A PLURALITY OF TRAY SECTIONDIVIDED FROM EACH OTHER ALONG RADIAL PLANES, AND POCKETS ADJACENT THEENDS OF THE DIVIDING WALLS OF SAID SECTION, A PLURALITY OF SPACERSPRINGS IN SAID POCKETS TO URGE SAID SECTIONS AWAY FROM EACH OTHERTRANSVERSELY OF SAID PLANES, A PLURALITY OF BOLTS TO HOLD SAID SECTIONSTOGETHER, A PRE-HEATER SECTION IN THE BOTTOM OF SAID TANK FORMED BY ACONCAVE WALL POSITIONED DIRECTLY BENEATH THE LOWEST TRAY AND SPACEDUPWARDLY FROM THE BOTTOM WALL OF THE TANK, A PIPE ASSEMBLY EXTENDINGFROM SAID PRE-HEATER SECTION TO THE TOP OF SAID TANK, AND HAVING OILDISCHARGE MEANS DIRECTING OIL INTO THE UPPERMOST OF SAID TRAYS, ANDHEATER MEANS ON THE OUTER SURFACE OF SAID SIDE WALL TO HEAT THE TRAYS.10. A VAPORIZER TRAY HAVING A SUBSTANTIALLY CIRCULAR PERIPHERY ANDFORMED BY MORE THAN TWO SUBSTANTIALLY IDENTICAL TRAY SECTIONS EACH OFWHICH HAS TWO RADIAL SIDE WALLS WITH EACH WALL HAVING ADJACENT ITS ENDSPOCKETS WHICH RECEIVE THE ENDS OF SPACER SPRINGS, AND MEANS HOLDING SAIDTRAY SECTIONS TOGETHER.